Do you need the Spitfire Symphony Orchestra Pro?
Obviously, I can't answer this for you but I can definitely show you what it brings to the table with its set of extended signals and microphone positions.
00:00 Cool jingle
00:06 The one question
01:37 Focusing on Spitfire Symphonic Strings
02:04 Why a comparison with BBCSO Pro
02:50 A rant about official demos
05:06 Processing the example track
07:19 Decca Tree
08:54 Close - Tree - Ambient
10:38 Outriggers
12:27 Stereo Mix: Fine
14:39 Stereo Mix: Medium
15:56 Stereo Mix: Broad
17:21 Stereo Pair - Leader
18:54 Close Ribbon - Stereo Pair - Gallery
20:39 BBCSO Pro
22:23 The various rants about the price
24:15 My conclusion